Scientific Method, term denoting the principles that guide scientific
research and experimentation, and also the philosophic bases of those
principles. Whereas philosophy in general is concerned with the why as
well as the how of things, science occupies itself with the latter
question only, but in a scrupulously rigorous manner. The era of modern
science is generally considered to have begun with the Renaissance, but
the rudiments of the scientific approach to knowledge can be observed
throughout human history.

Definitions of scientific method use such concepts as objectivity of
approach to and acceptability of the results of scientific study.
Objectivity indicates the attempt to observe things as they are, without
falsifying observations to accord with some preconceived world view.
Acceptability is judged in terms of the degree to which observations and
experimentations can be reproduced. Scientific method also involves the
interplay of inductive reasoning (reasoning from specific observations
and experiments to more general hypotheses and theories) and deductive
reasoning (reasoning from theories to account for specific experimental
results). By such reasoning processes, science attempts to develop the
broad laws—such as Isaac Newton’s law of gravitation—that become part of
our understanding of the natural world.

Science has tremendous scope, however, and its many separate
disciplines can differ greatly in terms of subject matter and the
possible ways of studying that subject matter. No single path to
discovery exists in science, and no one clear-cut description can be
given that accounts for all the ways in which scientific truth is
pursued. One of the early writers on scientific method, the English
philosopher and statesman Francis Bacon, wrote in the early 17th century
that a tabulation of a sufficiently large number of observations of
nature would lead to theories accounting for those operations—the method
of inductive reasoning. At about the same time, however, the French
mathematician and philosopher René Descartes was attempting to account
for observed phenomena on the basis of what he called clear and distinct
ideas—the method of deductive reasoning.

A closer approach to the method commonly used by physical scientists
today was that followed by Galileo in his study of falling bodies.
Observing that heavy objects fall with increasing speed, he formulated
the hypothesis that the speed attained is directly proportional to the
distance traversed. Being unable to test this directly, he deduced from
his hypothesis the conclusion that objects falling unequal distances
require the same amount of elapsed time. This was a false conclusion,
and hence, logically, the first hypothesis was false. Therefore Galileo
framed a new hypothesis: that the speed attained is directly
proportional to the time elapsed, not the distance traversed. From this
he was able to infer that the distance traversed by a falling object is
proportional to the square of the time elapsed, and this hypothesis he
was able to verify experimentally by rolling balls down an inclined
plane.

Such agreement of a conclusion with an actual observation does not
itself prove the correctness of the hypothesis from which the conclusion
is derived. It simply renders the premise that much more plausible. The
ultimate test of the validity of a scientific hypothesis is its
consistency with the totality of other aspects of the scientific
framework. This inner consistency constitutes the basis for the concept
of causality in science, according to which every effect is assumed to
be linked with a cause.

Scientists, like other human beings, may individually be swayed by
some prevailing worldview to look for certain experimental results
rather than others, or to "intuit” some broad theory that they then seek
to prove. The scientific community as a whole, however, judges the work
of its members by the objectivity and rigor with which that work has
been conducted; in this way the scientific method prevails.